本文使用了直接模拟(DNS)程序计算了三维超声速湍流射流火焰。首先介绍了本程序使用到的计算方法,包括热物性参数和输运参数的计算、反应机理、边界条件、离散方法。然后,本文使用该方法计算了马赫数为1.2的三维超声速H_2-AIR湍流射流火焰,描述了火焰的整作结构。最后,本文对火焰底部的稳燃的机理—自燃进行了分析和论证。 This article uses Direct Simulations (DNS) to calculate the 3D supersonic turbulent jet flame. First of all, the calculation methods used in this program are introduced, including calculation of thermophysical parameters and transport parameters, reaction mechanism, boundary conditions and discrete methods. Then, this method is used to calculate the three-dimensional hypersonic H_2-AIR turbulent jet flame with a Mach number of 1.2, and the whole structure of the flame is described. Finally, the mechanism of spontaneous combustion at the bottom of flame is analyzed and demonstrated.